package 笔试2.滴滴.one;


import java.util.Arrays;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

/*
5
1.3 2 1.5 1.3 1.50
 */
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        sc.nextLine();
        String s = sc.nextLine();
//        System.out.println(N+"/n"+s);
        String[] ss = s.split(" ");
        double[] nums = new double[N];
        for(int i=0;i<ss.length;i++){
            nums[i]=Double.parseDouble(ss[i]);
        }
//        System.out.println(Arrays.toString(nums));
        Arrays.sort(nums);
//        System.out.println(Arrays.toString(nums));

        Set<Double> set = new HashSet<>();
        for(double x:nums){
            set.add(x);
        }
        System.out.println(set.size());
    }

}
